RF Wireless Kernel Module For Raspberry Pi, BeagleBone And Others

June 27, 2013 by Mike Szczys 21 Comments

rfm12b-kernel-module

If you’ve done any wireless work with hobby electronics you probably recognize this part. The green PCB is an RFM12B wireless board. They come in a few different operating bandwidths, the 433 MHz is probably the most common. They’re super easy to interface with a small microcontroller but what about an embedded Linux board? That is the focus of this project, which builds a kernel driver for the RF module.

You can get your own RFM12B for a few bucks. They’re quite versatile when paired, but a lot of inexpensive wireless consumer goods operate on this band so the board can be used to send commands to wireless outlets, light fixtures, etc. [Georg] has been working with the BeagleBone, BeagleBone Black, and Raspberry Pi. His software package lets you build a kernel module to add an entry for the device into the /dev directory of a Linux system. So far the three boards listed are all that’s supported, but if you have five I/O pins available it should be a snap to tailor this to other hardware.

Wondering what else you can do with the setup? This will get the receiving end of a text-messaging doorbell up and running in no time.

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TI’s CC3000 WiFi Chip Gets A Library

June 24, 2013 by Brian Benchoff 43 Comments

About six months ago, Texas Instruments released a simple, cheap, single-chip WiFi module. At $10 a piece in quantities of 1000, the CC3000 is a much better solution to the problem of an ‘Internet of Things’ than a $50 Arduino Ethernet modules, or even the $30 Electric Imp. All indications, especially the frequent out of stock status for the dev board on TI’s web site, show the CC3000 will be a popular chip, but until now we haven’t seen a CC3000 library for the Arduino or other microcontrollers.

[Chris] just solved that problem for us with a CC3000 WiFi library for the Arduino. He ported TI’s MSP430 CC3000 library to the Arduino, allowing even the bare-bones Arduino Uno to connect to a WiFi network with just a handful of parts. The code itself takes about 12k of Flash and 350 bytes of RAM, giving anyone using the CC3000 enough room left over to do some really interesting stuff. There’s even a slimmed down library that uses somewhere between 2k and 6k of Flash, making an ATtiny-powered web server a reality.

There are a few caveats in using the CC3000 with an Arduino; it’s a 3.3 Volt part, so you’ll need a level shifter or some resistors. Also, the chip draws about 250 mA when it’s being used, so you’ll need a beefy battery if you want your project to last an entire day of use.

Now that the library is out of the way, be on the lookout for a CC3000 breakout board. Here’s one, but expect some more on the market soon.

Letting Bluetooth Take The Wires Out Of Your Headphones

June 17, 2013 by Mike Szczys 11 Comments

bt-wireless-headphones

This picture shows the gist of [Alan’s] hack to transition his wired headphone to internalize a Bluetooth audio receiver (translated).

He starts with a pair of wired “ear muff” style headphones and an aftermarket Bluetooth audio adapter that he’s been using with them. But if you’re not going to plug them into the audio source why have six feet of extra wire hanging about? [Alan] ditched the plastic case surrounding the Bluetooth hardware and cracked open the earpieces to find room for it. It’s a tight fit but there was just enough room.

It is unfortunate that the headphone design doesn’t already have a wired crossover hidden in the arc connecting the earpieces. Alan strung some of that red wire himself to connect the two speakers. The board is mounted so that the USB port is located where the wires used to enter the plastic body. This makes it a snap to plug them in when they need a recharge.

You can play a little “Where’s Waldo” with this one by trying to spot the Raspberry Pi in his build log.

Wireless Unread Email Counter Tells You How Busy You’re Not

June 8, 2013 by Brian Benchoff 12 Comments

counter

One of the marks of how busy you are – or how well your spam filters are set up – is how many unread emails you have in your inbox. [trumpkin] over on Instructables posted a great tutorial for making a wireless counter that displays the number of unread emails in your Gmail account.

[trumpkin] used a tiny and inexpensive 419 MHz transmitter and receiver combo to make this project work. On his desktop, he wired up a USB to UART bridge attached to the transmitter. For the receiver side, an ATMega328 reads the data coming off the receiver and displays the number of unread emails on two seven-segment displays.

The wireless device runs off of two AA batteries and should provide enough power to keep the email monitor running for a long time. More than enough time for your inbox to fill up and for you to become overwhelmed with the work you should be doing.

Wireless Microcontroller/PC Interface For $3

May 19, 2013 by Brian Benchoff 48 Comments

Sending data from a microcontroller to a PC usually requires some sort of serial connection, either through fiddly on-chip USB, FTDI chips, or expensive radio ICs. [Scott] didn’t want to deal with this when creating a network of wireless temperature sensors, so he hacked up a few cheap 433 MHz radio transmitters and receivers to transmit data to a PC for about $3.

After sensor data is collected on a microcontroller and sent over radio, there’s still the issue of getting it into a PC. For this, [Scott] piped the data into the microphone port of a cheap USB sound card. We’ve seen this trick before both in the world of microcontrollers and loading programs onto a Commodore 64 via a cassette interface.

Once the data is sent into the sound card, it’s decoded with a a small Python app. Given the range and quality of the RF transmitters and receivers [Scott] says it’s not an extremely reliable way to send data to a PC. It is cheap, though, and if you need to read sensors wirelessly on a budget, it’s hard to do much better.

Check out [Scott]’s demo of his creation below.

[youtube=http://www.youtube.com/watch?v=GJHFldPwZvM&w=580]

Wifi Pineapple Project Uses Updated Hardware For Man-in-the-middle Attacks

April 29, 2013 by Mike Szczys 38 Comments

We’ve seen this small, cheap, and powerful WiFi router before. But this time it’s up to no good. [Andy] used a TP-Link WR703N to build an upgraded WiFi Pineapple hacking tool.

A WiFi Pineapple is a device spawned years ago by the Hak5 team (here’s a clip showing off the device). It uses a WiFi router that will answer to any SSID request. Basically if your computer or smart phone has an AP SSID saved and broadcasts a request to connect the pineapple will pretend to be that device and start the handshake. This provides the chance to sniff all the data passing through in a classic man-in-the-middle attack.

[Andy] is recreating the device but at a rock bottom price. He picked up this router for about $20 and added an $8 USB drive to it. The only other thing you would need is a power source and a way to hide the hardware. The code used in the Hak5 version is available for download and that’s what he worked on after flashing OpenWrt to the device.

[Thanks Midnite]

Acrobatic Tricopter Inspired By The Oblivion Movie Trailer

April 24, 2013 by Mike Szczys 28 Comments

tricopter

There have been a ton of commercials for the new [Tom Cruise] movie called Oblivion. One of the main points in every clip we remember seeing is the Top Gun meets Star Trek vehicle he does some tricks in. [James Cotton] loved that footage and ended up building his own RC version of the vehicle.

Three propellers give it lift, with directional control facilitated by servo motors which can pivot the motors attached to the two orange propellers. This design produces remarkably responsive controls as shown in the video after the break. That being said it’s still not immune to operator error. At the end of the clip [James] crashes it hard, stripping out the gears on the servo motors.

He has a few things in mind for the future of the device (and he’ll have plenty of time to plan while he waits for replacement servos to arrive). The aircraft should be able to carry a camera long with it. He discusses the issues involved with where the camera ends up pointing based on what the tilting motors are doing. But we figure he could always build a base that lets the camera pan and tilt separately from the chassis.

You can find a few tricopter projects around here but we’ve always like the one made of cardboard.

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